These overload relays are similar to circuit breakers in construction and use, but most circuit breakers differ

in that they interrupt the circuit if overload occurs even for an instant. Thermal overload relays are conversely

designed to measure a motor's heating profile; therefore, overload must occur for an extended period before

the circuit is interrupted.

Applications:

UKH series overload relays apply to circuit of AC 50Hz or 60Hz, rated voltage to below 660V and rated current . 1A-800A for AC motor overload and open-phase protection during long time or intermittent long time service, which can also protect 3-phase serious imbalance and long starting time of motor or long timer operation, can also be used for corresponding AC contactor for electromagnetic starter.

Specifications:

Three-phase Balance Motion Time

No

Times of the setting current

Motion time

Start condition

Ambient temperature

1

1.05

>2h

Cold state

20±5oC

2

1.2

<2h

Heat state(Following the No.1 test)

3

1.5

<4min

4

7.2

10A

2s< Tp≤10s

≤63A

Cold state

10

4s< Tp≤10s

>63A

Features:

1. Direct mounting structure:

The thermal overload rela can be mounted directly to the Magnetic Contactors without